Explanation:
When we celebrate the start of 2019, on January 1 the
New Horizons spacecraft will
fly by Ultima Thule.
A world of the Kuiper belt 6.5 billion kilometers
from the Sun, the nickname
Ultima
Thule (catalog designation 2014 MU69) fittingly means "beyond
the known world".
Following its 2015
flyby of Pluto, New Horizons
was targeted for this journey, attempting the
most distant flyby for a spacecraft from Earth by
approaching Ultima Thule to within about 3500 kilometers.
The tiny world itself is about 30 kilometers in size.
In 2017 and 2018, observing campaigns with
Earth-based telescopes
determined the shape of the object to be a contact binary
or a close binary sytem as in this artist's illustration.
New Horizons will image close up its unexplored
surface in the dim light of the distant Sun.